iOS WKWebView緩存清理

1、在發起請求時直接從原始地址請求，不讀緩存數據 : NSURLRequestReloadIgnoringCacheData

    self.webView = [[WKWebView alloc]initWithFrame:f configuration:configuration];
    _webView.navigationDelegate = self;
    _webView.backgroundColor = [UIColor clearColor];
    _webView.allowsBackForwardNavigationGestures =YES;//打開網頁間的 滑動返回
    _webView.scrollView.decelerationRate = UIScrollViewDecelerationRateNormal;
    //監控進度
    [_webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
    [_webView addObserver:self forKeyPath:@"title" options:NSKeyValueObservingOptionNew context:nil];
    [self.view addSubview:_webView];
  //進度條
    _progressView = [[UIProgressView alloc]initWithProgressViewStyle:UIProgressViewStyleDefault];
    _progressView.tintColor = _progressViewColor;
    _progressView.trackTintColor = [UIColor clearColor];
    _progressView.frame = CGRectMake(0, 0, self.view.bounds.size.width, 3.0);
    [_webView addSubview:_progressView];

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:_url] cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:15.0];
    //加密header部分
    NSString *headerContentStr = [[HeaderModel new] modelToJSONString];
    NSString *headerAESStr = aesEncrypt(headerContentStr);
    [request setValue:headerAESStr forHTTPHeaderField:@"header-encrypt-code"];
    [_webView loadRequest:request];

2、清除緩存

    if(@available(iOS 9.0, *)) {
        NSSet *websiteDataTypes = [WKWebsiteDataStore allWebsiteDataTypes];
        NSDate *dateFrom = [NSDate dateWithTimeIntervalSince1970:0];
        [[WKWebsiteDataStore defaultDataStore] removeDataOfTypes:websiteDataTypes modifiedSince:dateFrom completionHandler:^{
            NSLog(@"清楚緩存完畢");
        }];
    }else{
        [[NSURLCache sharedURLCache] removeAllCachedResponses];
        [[NSURLCache sharedURLCache] setDiskCapacity:0];
        [[NSURLCache sharedURLCache] setMemoryCapacity:0];
    }